William "Jimmy" Hartwig (born 5 October 1954) is a retired German football player. He played for Kickers Offenbach, TSV 1860 München, Hamburger SV, 1. FC Köln and FC Homburg of the Bundesliga and for Austria Salzburg of Austria. The son of an African-American soldier and a German mother, Hartwig was one of the first black players in German and Austrian football.

Hartwig won the European Cup in 1983 with Hamburger SV, and was three times German league champion in 1979, 1982 und 1983 and three times league runner-up with Hamburger SV. He also earned two caps for the West German national team, making him only the second non-white player (after Erwin Kostedde) to achieve this feat.

After his playing career, Hartwig worked as a coach at FC Augsburg in 1989 and FC Sachsen Leipzig in 1990.[5] He entered the TV business, where he has been working ever since, whilst also appearing in the theatre as an actor.